CIT 594 Assignment 4: GUI Building in NetBeans
Spring 2008, David Matuszek


General Idea:

Create a GUI in NetBeans that can be used to control an animation.

Define an animation (at least "bouncing ball", but feel free to do something more interesting.)

Package your program as an executable .jar file, including your source files.



First, use NetBeans visual GUI editor to create the GUI for your project. Start by creating a new project, but instead of choosing Java Application, choose Java Desktop Application. Name your project Animation, and name your main class animation.Animation. This will start you in the GUI builder. Use it to create an interface that looks like this:

Animation window
(Click to view larger image)

Start by clicking in the center of the large area to select it. Then right-click it and set the layout to BorderLayout. Drag a JPanel to the SOUTH area, and using the information area on the right, find the name of this JPanel and change it to controlPanel. Drag another JPanel to the CENTER area, and name it displayPanel. Drag the appropriate components to the control panel and, for each component, set its text to the text you want on the component, and give it a meaningful name (for example, runButton).

Hint: When you get into a mess that you can't seem to get out of, select the project and delete it. Be sure to also delete the source files. Then you can start over. Using the GUI editor is tricky, so don't be too upset if it takes you several tries to get it right.

To attach a Listener to a button: Select and right-click the button, choose Properties, then action, then [...]. For Action:, choose Create New Action..., then for Action's Method:, type in the name of a method. This will bring you to the source code where the new method has been created.

Here's what the buttons are supposed to do:

The slider controls the speed of the animation, from very slow or stopped (at the left end) to very fast (at the right end). Do this by controlling the time between successive frames. Do not exceed 40 frames/second.

Implement the Exit and About... menu items. The About... menu item should include your name as author.

The animation

Provide an animation, using the Model-View-Controller and Observer design patterns, and controlled by a Timer. You will probably want to review my Animation slides from CIT591, and you may want to download the example code.

Do any animation you like. I recommend that you start with the basic bouncing ball animation, which is sort of the "Hello World" of animation programs. Once you get that running, you can either stop there, or replace it with something more interesting; at that point, all the basic structure will be in place.

The jar file

Jar files are like zip files. In fact, jar files are zip files. The difference is that a jar file can be executed by double-clicking on it--if (1) you have Java properly installed on your machine (try entering java  -version in a DOS window), and (2) if you have set up the jar file properly.

In Eclipse you would Export your program as a jar file, and follow the prompts. In Netbeans there is already a jar file, but you have to fiddle with it. In NetBeans, choose Help > Help Contents > Java Applications > Building Java Applications > Building a jar file.

Hint: After making the jar file, it's a good idea to make a copy of it, rename the copy to have the .zip extension instead of the .jar extension, and unzip it to be sure everything is there that's supposed to be there. If you are missing anything (especially source files), or if we can't run your jar file, you will lose points.

The Eclipse alternative

NetBeans comes with a visual GUI editor, and Eclipse doesn't. However, you can download one, as a plugin, from Using it is very similar to using the one in NetBeans; I don't know which one is less buggy.

Due date:

Build a jar containing everything in the complete NetBeans project, including all your source files, and submit via Blackboard before midnight Thursday, February 14.